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排序方式: 共有3707条查询结果,搜索用时 15 毫秒
941.
Let Ω⊂Cn be a bounded starlike circular domain with 0∈Ω. In this paper, we introduce a class of holomorphic mappings Mg on Ω. Let f(z) be a normalized locally biholomorphic mapping on Ω such that and z=0 is the zero of order k+1 of f(z)−z. We obtain a sharp growth theorem and sharp coefficient bounds for f(z). As applications, sharp distortion theorems for a subclass of starlike mappings are obtained. These results unify and generalize many known results. 相似文献
942.
Maxim V. Balashov 《Journal of Mathematical Analysis and Applications》2010,371(1):113-537
We consider a definition of a weakly convex set which is a generalization of the notion of a weakly convex set in the sense of Vial and a proximally smooth set in the sense of Clarke, from the case of the Hilbert space to a class of Banach spaces with the modulus of convexity of the second order. Using the new definition of the weakly convex set with the given modulus of nonconvexity we prove a new retraction theorem and we obtain new results about continuity of the intersection of two continuous set-valued mappings (one of which has nonconvex images) and new affirmative solutions of the splitting problem for selections. We also investigate relationship between the new definition and the definition of a proximally smooth set and a smooth set. 相似文献
943.
Suppose that A is an operator algebra on a Hilbert space H. An element V in A is called an all-derivable point of A for the strong operator topology if every strong operator topology continuous derivable mapping φ at V is a derivation. Let N be a complete nest on a complex and separable Hilbert space H. Suppose that M belongs to N with {0}≠M≠H and write for M or M⊥. Our main result is: for any with , if is invertible in , then Ω is an all-derivable point in for the strong operator topology. 相似文献
944.
On the number of transversals in Cayley tables of cyclic groups 总被引:1,自引:0,他引:1
It is well known that if n is even, the addition table for the integers modulo n (which we denote by Bn) possesses no transversals. We show that if n is odd, then the number of transversals in Bn is at least exponential in n. Equivalently, for odd n, the number of diagonally cyclic latin squares of order n, the number of complete mappings or orthomorphisms of the cyclic group of order n, the number of magic juggling sequences of period n and the number of placements of n non-attacking semi-queens on an n×n toroidal chessboard are at least exponential in n. For all large n we show that there is a latin square of order n with at least (3.246)n transversals.We diagnose all possible sizes for the intersection of two transversals in Bn and use this result to complete the spectrum of possible sizes of homogeneous latin bitrades.We also briefly explore potential applications of our results in constructing random mutually orthogonal latin squares. 相似文献
945.
Hendrik Luit Wietsma 《Indagationes Mathematicae》2018,29(3):997-1008
A new characterization of generalized Nevanlinna functions in terms of multivalency is established. By analyzing multivalent functions additional novel characterizations of (generalized) Nevanlinna functions are obtained. As a particular consequence of these investigations a function-theoretic proof of the factorization property of generalized Nevanlinna functions is obtained. 相似文献
946.
In this paper, we investigate the Hyers-Ulam stability of the following function equation 2f(2x + y) + 2f(2x - y) = 4f(x + y) + 4f(x - y) + 4f(2x) + f(2y) - Sf(x) - 8f(y) in quasi-β-normed spaces. 相似文献
947.
平面上的射影变换,将二阶曲线变为另一二阶曲线,这个射影变换也可以称为这两个二阶曲线间的射影映射.若两个二阶曲线相切,则存在以切点为射影中心的两个二阶曲线间的射影映射;若两个二阶曲线相离,则存在以两个二阶曲线公切线交点为射影中心的射影映射;若两个二阶曲线相交,则存在以其中一交点为射影中心的两个二阶曲线间的射影映射. 相似文献
948.
949.
半模糊凸模糊映射 总被引:1,自引:1,他引:0
In this paper, a new class of fuzzy mappings called semistrictly convex fuzzy mappings is introduced and we present some properties of this kind of fuzzy mappings. In particular, we prove that a local minimum of a semistrictly convex fuzzy mapping is also a global minimum. We also discuss the relations among convexity, strict convexity and semistrict convexity of fuzzy mapping, and give several sufficient conditions for convexity and semistrict convexity. 相似文献
950.
Using perturbation results on the sums of ranges of nonlinear accretive mappings of Calvert and Gupta, we present some abstract results for the existence of the solutions of nonlinear Neumann elliptic systems which is related to the so-called generalized (p, q)-Laplacian in this paper. The systems discussed in this paper and the method used extend and complement some of the previous work. 相似文献